Java tutorial
/* * Copyright (C) 2013 Andreas Stuetz <andreas.stuetz@gmail.com> * * Licensed under the Apache License, Version 2.0 (the "License"); * you may not use this file except in compliance with the License. * You may obtain a copy of the License at * * http://www.apache.org/licenses/LICENSE-2.0 * * Unless required by applicable law or agreed to in writing, software * distributed under the License is distributed on an "AS IS" BASIS, * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. * See the License for the specific language governing permissions and * limitations under the License. */ package com.lizhi.library.widget; import android.app.Activity; import android.content.Context; import android.content.res.TypedArray; import android.graphics.Canvas; import android.graphics.Color; import android.graphics.Paint; import android.graphics.Paint.Style; import android.graphics.Typeface; import android.os.Build; import android.os.Parcel; import android.os.Parcelable; import android.support.v4.view.ViewPager; import android.support.v4.view.ViewPager.OnPageChangeListener; import android.util.AttributeSet; import android.util.DisplayMetrics; import android.util.TypedValue; import android.view.Gravity; import android.view.View; import android.view.ViewTreeObserver.OnGlobalLayoutListener; import android.widget.HorizontalScrollView; import android.widget.ImageButton; import android.widget.LinearLayout; import android.widget.TextView; import com.lizhi.library.R; import com.lizhi.library.utils.LZUtils; import java.util.Locale; public class WechatTab extends HorizontalScrollView { private int visibleItemCount = 0; //?? public interface IconTabProvider { public int getPageIconResId(int position); } // @formatter:off private static final int[] ATTRS = new int[] { android.R.attr.textSize, android.R.attr.textColor }; // @formatter:on private LinearLayout.LayoutParams defaultTabLayoutParams; private LinearLayout.LayoutParams expandedTabLayoutParams; private LinearLayout.LayoutParams fixTabLayoutParams; private final PageListener pageListener = new PageListener(); public OnPageChangeListener delegatePageListener; private LinearLayout tabsContainer; private ViewPager pager; private int tabCount; private int currentPosition = 0; private int selectedPosition = 0; private float currentPositionOffset = 0f; private Paint rectPaint; private Paint dividerPaint; private int indicatorColor = 0xFF666666; private int underlineColor = 0x1A000000; private int dividerColor = 0x1A000000; private boolean shouldExpand = false; private boolean textAllCaps = true; private boolean underLine = true; private boolean clickable = true; private int scrollOffset = 52; private int indicatorHeight = 2; private int underlineHeight = 2; private int dividerPadding = 12; private int tabPadding = 3; // tab textview padding private int dividerWidth = 1; private int mMyUnderlinePadding = 12; private int tabTextSize = 12; private int tabTextColor = 0xFF666666; private int selectedTabTextColor = 0xFF666666; private Typeface tabTypeface = null; private int tabTypefaceStyle = Typeface.NORMAL; private int lastScrollX = 0; private int tabBackgroundResId = R.drawable.wechat_tab_bg; private Locale locale; public WechatTab(Context context) { this(context, null); } public WechatTab(Context context, AttributeSet attrs) { this(context, attrs, 0); } public WechatTab(Context context, AttributeSet attrs, int defStyle) { super(context, attrs, defStyle); setFillViewport(true); setWillNotDraw(false); tabsContainer = new LinearLayout(context); tabsContainer.setOrientation(LinearLayout.HORIZONTAL); tabsContainer.setLayoutParams(new LayoutParams(LayoutParams.MATCH_PARENT, LayoutParams.MATCH_PARENT)); addView(tabsContainer); DisplayMetrics dm = getResources().getDisplayMetrics(); scrollOffset = (int) TypedValue.applyDimension(TypedValue.COMPLEX_UNIT_DIP, scrollOffset, dm); indicatorHeight = (int) TypedValue.applyDimension(TypedValue.COMPLEX_UNIT_DIP, indicatorHeight, dm); underlineHeight = (int) TypedValue.applyDimension(TypedValue.COMPLEX_UNIT_DIP, underlineHeight, dm); dividerPadding = (int) TypedValue.applyDimension(TypedValue.COMPLEX_UNIT_DIP, dividerPadding, dm); tabPadding = (int) TypedValue.applyDimension(TypedValue.COMPLEX_UNIT_DIP, tabPadding, dm); dividerWidth = (int) TypedValue.applyDimension(TypedValue.COMPLEX_UNIT_DIP, dividerWidth, dm); tabTextSize = (int) TypedValue.applyDimension(TypedValue.COMPLEX_UNIT_SP, tabTextSize, dm); // get system attrs (android:textSize and android:textColor) TypedArray a = context.obtainStyledAttributes(attrs, ATTRS); tabTextSize = a.getDimensionPixelSize(0, tabTextSize); tabTextColor = a.getColor(1, tabTextColor); a.recycle(); // get custom attrs a = context.obtainStyledAttributes(attrs, R.styleable.WechatTab); clickable = a.getBoolean(R.styleable.WechatTab_pstsClickable, clickable); selectedTabTextColor = a.getColor(R.styleable.WechatTab_pstsSelectedTabTextColor, selectedTabTextColor); visibleItemCount = a.getInteger(R.styleable.WechatTab_pstsVisibleCount, visibleItemCount); indicatorColor = a.getColor(R.styleable.WechatTab_pstsIndicatorColorWe, indicatorColor); underlineColor = a.getColor(R.styleable.WechatTab_pstsUnderlineColorWe, underlineColor); underLine = a.getBoolean(R.styleable.WechatTab_pstsUnderline, underLine); dividerColor = a.getColor(R.styleable.WechatTab_pstsDividerColorWe, dividerColor); indicatorHeight = a.getDimensionPixelSize(R.styleable.WechatTab_pstsIndicatorHeightWe, indicatorHeight); underlineHeight = a.getDimensionPixelSize(R.styleable.WechatTab_pstsUnderlineHeightWe, underlineHeight); dividerPadding = a.getDimensionPixelSize(R.styleable.WechatTab_pstsDividerPaddingWe, dividerPadding); tabPadding = a.getDimensionPixelSize(R.styleable.WechatTab_pstsTabPaddingLeftRightWe, tabPadding); tabBackgroundResId = a.getResourceId(R.styleable.WechatTab_pstsTabBackgroundWe, tabBackgroundResId); shouldExpand = a.getBoolean(R.styleable.WechatTab_pstsShouldExpandWe, shouldExpand); scrollOffset = a.getDimensionPixelSize(R.styleable.WechatTab_pstsScrollOffsetWe, scrollOffset); textAllCaps = a.getBoolean(R.styleable.WechatTab_pstsTextAllCapsWe, textAllCaps); mMyUnderlinePadding = (int) TypedValue.applyDimension(TypedValue.COMPLEX_UNIT_DIP, mMyUnderlinePadding, dm); a.recycle(); rectPaint = new Paint(); rectPaint.setAntiAlias(true); rectPaint.setStyle(Style.FILL); dividerPaint = new Paint(); dividerPaint.setAntiAlias(true); dividerPaint.setStrokeWidth(dividerWidth); if (visibleItemCount != 0) fixTabLayoutParams = new LinearLayout.LayoutParams(getScreenWidth(context) / visibleItemCount, LayoutParams.MATCH_PARENT); defaultTabLayoutParams = new LinearLayout.LayoutParams(LayoutParams.WRAP_CONTENT, LayoutParams.MATCH_PARENT); expandedTabLayoutParams = new LinearLayout.LayoutParams(0, LayoutParams.MATCH_PARENT, 1.0f); if (locale == null) { locale = getResources().getConfiguration().locale; } } public void setVisibleItems(int count) { visibleItemCount = count; } private void setTabsValue() { DisplayMetrics dm = getResources().getDisplayMetrics(); // Tab? setShouldExpand(true); // Tab? setDividerColor(Color.TRANSPARENT); // Tab setUnderlineHeight((int) TypedValue.applyDimension(TypedValue.COMPLEX_UNIT_DIP, 1, dm)); // Tab Indicator setIndicatorHeight((int) TypedValue.applyDimension(TypedValue.COMPLEX_UNIT_DIP, 3, dm)); // Tab? setTextSize((int) TypedValue.applyDimension(TypedValue.COMPLEX_UNIT_SP, 16, dm)); // Tab Indicator //TODO // setIndicatorColor(getResources().getColor(R.color.theme_color)); // Tab () //TODO // setSelectedTextColor(getResources().getColor(R.color.theme_color)); // ?Tab setTabBackground(0); } public void setViewPager(ViewPager pager) { this.pager = pager; if (pager.getAdapter() == null) { throw new IllegalStateException("ViewPager does not have adapter instance."); } pager.setOnPageChangeListener(pageListener); notifyDataSetChanged(); setTabsValue(); } public void setOnPageChangeListener(OnPageChangeListener listener) { this.delegatePageListener = listener; } public void notifyDataSetChanged() { tabsContainer.removeAllViews(); tabCount = pager.getAdapter().getCount(); for (int i = 0; i < tabCount; i++) { if (pager.getAdapter() instanceof IconTabProvider) { addIconTab(i, ((IconTabProvider) pager.getAdapter()).getPageIconResId(i)); } else { addTextTab(i, pager.getAdapter().getPageTitle(i).toString()); } } updateTabStyles(); getViewTreeObserver().addOnGlobalLayoutListener(new OnGlobalLayoutListener() { @Override public void onGlobalLayout() { getViewTreeObserver().removeGlobalOnLayoutListener(this); currentPosition = pager.getCurrentItem(); scrollToChild(currentPosition, 0); } }); } private void addTextTab(final int position, String title) { TextView tab = new TextView(getContext()); tab.setText(title); tab.setGravity(Gravity.CENTER); tab.setSingleLine(); addTab(position, tab); } private void addIconTab(final int position, int resId) { ImageButton tab = new ImageButton(getContext()); tab.setImageResource(resId); addTab(position, tab); } private void addTab(final int position, View tab) { tab.setFocusable(true); tab.setOnClickListener(new OnClickListener() { @Override public void onClick(View v) { if (clickable) pager.setCurrentItem(position, false); } }); tab.setPadding(tabPadding, 0, tabPadding, 0); tabsContainer.addView(tab, position, visibleItemCount != 0 ? fixTabLayoutParams : defaultTabLayoutParams); } private void updateTabStyles() { for (int i = 0; i < tabCount; i++) { View v = tabsContainer.getChildAt(i); v.setBackgroundResource(tabBackgroundResId); if (v instanceof TextView) { TextView tab = (TextView) v; tab.setTextSize(TypedValue.COMPLEX_UNIT_PX, tabTextSize); tab.setTypeface(tabTypeface, tabTypefaceStyle); tab.setTextColor(tabTextColor); // setAllCaps() is only available from API 14, so the upper case is made manually if we are on a // pre-ICS-build if (textAllCaps) { if (Build.VERSION.SDK_INT >= Build.VERSION_CODES.ICE_CREAM_SANDWICH) { tab.setAllCaps(true); } else { tab.setText(tab.getText().toString().toUpperCase(locale)); } } if (i == selectedPosition) { tab.setTextColor(selectedTabTextColor); } } } } private void scrollToChild(int position, int offset) { if (tabCount == 0) { return; } int newScrollX = tabsContainer.getChildAt(position).getLeft() + offset; if (position > 0 || offset > 0) { newScrollX -= scrollOffset; } if (newScrollX != lastScrollX) { lastScrollX = newScrollX; scrollTo(newScrollX, 0); } } @Override protected void onDraw(Canvas canvas) { super.onDraw(canvas); if (isInEditMode() || tabCount == 0) { return; } final int height = getHeight(); // draw underline rectPaint.setColor(underlineColor); canvas.drawRect(0, height - underlineHeight, tabsContainer.getWidth(), height, rectPaint); // draw indicator line rectPaint.setColor(indicatorColor); // default: line below current tab View currentTab = tabsContainer.getChildAt(currentPosition); float lineLeft = currentTab.getLeft(); float lineRight = currentTab.getRight(); // if there is an offset, start interpolating left and right coordinates between current and next tab if (currentPositionOffset > 0f && currentPosition < tabCount - 1) { View nextTab = tabsContainer.getChildAt(currentPosition + 1); final float nextTabLeft = nextTab.getLeft(); final float nextTabRight = nextTab.getRight(); lineLeft = (currentPositionOffset * nextTabLeft + (1f - currentPositionOffset) * lineLeft); lineRight = (currentPositionOffset * nextTabRight + (1f - currentPositionOffset) * lineRight); } // TextView tv = ((TextView) currentTab); // String s = tv.getText().toString(); // float widths[] = new float[s.length()]; // tv.getPaint().getTextWidths(s, widths); // float StringWidth = 0; // for (float item : widths) { // StringWidth += item; // } // int padding = (int) ((tv.getWidth() - StringWidth) / 2 - mMyUnderlinePadding); // if (padding < 0) { // padding = 0; // } if (!underLine) { canvas.drawRect(lineLeft, 0, lineRight, height, rectPaint); } else { canvas.drawRect(lineLeft + mMyUnderlinePadding, height - indicatorHeight, lineRight - mMyUnderlinePadding, height, rectPaint); } // draw divider dividerPaint.setColor(dividerColor); for (int i = 0; i < tabCount - 1; i++) { View tab = tabsContainer.getChildAt(i); canvas.drawLine(tab.getRight(), dividerPadding, tab.getRight(), height - dividerPadding, dividerPaint); } } private class PageListener implements OnPageChangeListener { @Override public void onPageScrolled(int position, float positionOffset, int positionOffsetPixels) { currentPosition = position; currentPositionOffset = positionOffset; scrollToChild(position, (int) (positionOffset * tabsContainer.getChildAt(position).getWidth())); invalidate(); if (delegatePageListener != null) { delegatePageListener.onPageScrolled(position, positionOffset, positionOffsetPixels); } } @Override public void onPageScrollStateChanged(int state) { if (state == ViewPager.SCROLL_STATE_IDLE) { scrollToChild(pager.getCurrentItem(), 0); } if (delegatePageListener != null) { delegatePageListener.onPageScrollStateChanged(state); } } @Override public void onPageSelected(int position) { selectedPosition = position; updateTabStyles(); if (delegatePageListener != null) { delegatePageListener.onPageSelected(position); } } } public void setIndicatorColor(int indicatorColor) { this.indicatorColor = indicatorColor; invalidate(); } public void setIndicatorColorResource(int resId) { this.indicatorColor = getResources().getColor(resId); invalidate(); } public int getIndicatorColor() { return this.indicatorColor; } public void setIndicatorHeight(int indicatorLineHeightPx) { this.indicatorHeight = indicatorLineHeightPx; invalidate(); } public int getIndicatorHeight() { return indicatorHeight; } public void setUnderlineColor(int underlineColor) { this.underlineColor = underlineColor; invalidate(); } public void setUnderlineColorResource(int resId) { this.underlineColor = getResources().getColor(resId); invalidate(); } public int getUnderlineColor() { return underlineColor; } public void setDividerColor(int dividerColor) { this.dividerColor = dividerColor; invalidate(); } public void setDividerColorResource(int resId) { this.dividerColor = getResources().getColor(resId); invalidate(); } public int getDividerColor() { return dividerColor; } public void setUnderlineHeight(int underlineHeightPx) { this.underlineHeight = underlineHeightPx; invalidate(); } public int getUnderlineHeight() { return underlineHeight; } public void setDividerPadding(int dividerPaddingPx) { this.dividerPadding = dividerPaddingPx; invalidate(); } public int getDividerPadding() { return dividerPadding; } public void setScrollOffset(int scrollOffsetPx) { this.scrollOffset = scrollOffsetPx; invalidate(); } public int getScrollOffset() { return scrollOffset; } public void setShouldExpand(boolean shouldExpand) { this.shouldExpand = shouldExpand; notifyDataSetChanged(); } public boolean getShouldExpand() { return shouldExpand; } public boolean isTextAllCaps() { return textAllCaps; } public void setAllCaps(boolean textAllCaps) { this.textAllCaps = textAllCaps; } public void setTextSize(int textSizePx) { this.tabTextSize = textSizePx; updateTabStyles(); } public void setUnderlinePadding0() { mMyUnderlinePadding = 0; } public int getTextSize() { return tabTextSize; } public void setTextColor(int textColor) { this.tabTextColor = textColor; updateTabStyles(); } public void setTextColorResource(int resId) { this.tabTextColor = getResources().getColor(resId); updateTabStyles(); } public int getTextColor() { return tabTextColor; } public void setSelectedTextColor(int textColor) { this.selectedTabTextColor = textColor; updateTabStyles(); } public void setSelectedTextColorResource(int resId) { this.selectedTabTextColor = getResources().getColor(resId); updateTabStyles(); } public int getSelectedTextColor() { return selectedTabTextColor; } public void setTypeface(Typeface typeface, int style) { this.tabTypeface = typeface; this.tabTypefaceStyle = style; updateTabStyles(); } public void setTabBackground(int resId) { this.tabBackgroundResId = resId; updateTabStyles(); } public int getTabBackground() { return tabBackgroundResId; } public void setTabPaddingLeftRight(int paddingPx) { this.tabPadding = paddingPx; updateTabStyles(); } public int getTabPaddingLeftRight() { return tabPadding; } @Override public void onRestoreInstanceState(Parcelable state) { SavedState savedState = (SavedState) state; super.onRestoreInstanceState(savedState.getSuperState()); currentPosition = savedState.currentPosition; requestLayout(); } @Override public Parcelable onSaveInstanceState() { Parcelable superState = super.onSaveInstanceState(); SavedState savedState = new SavedState(superState); savedState.currentPosition = currentPosition; return savedState; } static class SavedState extends BaseSavedState { int currentPosition; public SavedState(Parcelable superState) { super(superState); } private SavedState(Parcel in) { super(in); currentPosition = in.readInt(); } @Override public void writeToParcel(Parcel dest, int flags) { super.writeToParcel(dest, flags); dest.writeInt(currentPosition); } public static final Creator<SavedState> CREATOR = new Creator<SavedState>() { @Override public SavedState createFromParcel(Parcel in) { return new SavedState(in); } @Override public SavedState[] newArray(int size) { return new SavedState[size]; } }; } private float dipToPix(Context context, float dipValue) { DisplayMetrics metrics = context.getResources().getDisplayMetrics(); return TypedValue.applyDimension(TypedValue.COMPLEX_UNIT_DIP, dipValue, metrics); } private int getScreenWidth(Context context) { DisplayMetrics displaymetrics = new DisplayMetrics(); ((Activity) context).getWindowManager().getDefaultDisplay().getMetrics(displaymetrics); int height = displaymetrics.heightPixels; int width = displaymetrics.widthPixels; return width; } }