Java tutorial
/* * Copyright (C) 2006 The Android Open Source Project * * 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 android.support.v7.view.menu; import android.content.Context; import android.graphics.drawable.Drawable; import android.support.annotation.RestrictTo; import android.support.v4.view.ViewCompat; import android.support.v7.appcompat.R; import android.support.v7.widget.TintTypedArray; import android.util.AttributeSet; import android.view.LayoutInflater; import android.view.View; import android.view.ViewGroup; import android.widget.CheckBox; import android.widget.CompoundButton; import android.widget.ImageView; import android.widget.LinearLayout; import android.widget.RadioButton; import android.widget.TextView; import static android.support.annotation.RestrictTo.Scope.GROUP_ID; /** * The item view for each item in the ListView-based MenuViews. * * @hide */ @RestrictTo(GROUP_ID) public class ListMenuItemView extends LinearLayout implements MenuView.ItemView { private static final String TAG = "ListMenuItemView"; private MenuItemImpl mItemData; private ImageView mIconView; private RadioButton mRadioButton; private TextView mTitleView; private CheckBox mCheckBox; private TextView mShortcutView; private ImageView mSubMenuArrowView; private Drawable mBackground; private int mTextAppearance; private Context mTextAppearanceContext; private boolean mPreserveIconSpacing; private Drawable mSubMenuArrow; private int mMenuType; private LayoutInflater mInflater; private boolean mForceShowIcon; public ListMenuItemView(Context context, AttributeSet attrs) { this(context, attrs, R.attr.listMenuViewStyle); } public ListMenuItemView(Context context, AttributeSet attrs, int defStyleAttr) { super(context, attrs); final TintTypedArray a = TintTypedArray.obtainStyledAttributes(getContext(), attrs, R.styleable.MenuView, defStyleAttr, 0); mBackground = a.getDrawable(R.styleable.MenuView_android_itemBackground); mTextAppearance = a.getResourceId(R.styleable.MenuView_android_itemTextAppearance, -1); mPreserveIconSpacing = a.getBoolean(R.styleable.MenuView_preserveIconSpacing, false); mTextAppearanceContext = context; mSubMenuArrow = a.getDrawable(R.styleable.MenuView_subMenuArrow); a.recycle(); } @Override protected void onFinishInflate() { super.onFinishInflate(); ViewCompat.setBackground(this, mBackground); mTitleView = (TextView) findViewById(R.id.title); if (mTextAppearance != -1) { mTitleView.setTextAppearance(mTextAppearanceContext, mTextAppearance); } mShortcutView = (TextView) findViewById(R.id.shortcut); mSubMenuArrowView = (ImageView) findViewById(R.id.submenuarrow); if (mSubMenuArrowView != null) { mSubMenuArrowView.setImageDrawable(mSubMenuArrow); } } public void initialize(MenuItemImpl itemData, int menuType) { mItemData = itemData; mMenuType = menuType; setVisibility(itemData.isVisible() ? View.VISIBLE : View.GONE); setTitle(itemData.getTitleForItemView(this)); setCheckable(itemData.isCheckable()); setShortcut(itemData.shouldShowShortcut(), itemData.getShortcut()); setIcon(itemData.getIcon()); setEnabled(itemData.isEnabled()); setSubMenuArrowVisible(itemData.hasSubMenu()); } public void setForceShowIcon(boolean forceShow) { mPreserveIconSpacing = mForceShowIcon = forceShow; } public void setTitle(CharSequence title) { if (title != null) { mTitleView.setText(title); if (mTitleView.getVisibility() != VISIBLE) mTitleView.setVisibility(VISIBLE); } else { if (mTitleView.getVisibility() != GONE) mTitleView.setVisibility(GONE); } } public MenuItemImpl getItemData() { return mItemData; } public void setCheckable(boolean checkable) { if (!checkable && mRadioButton == null && mCheckBox == null) { return; } // Depending on whether its exclusive check or not, the checkbox or // radio button will be the one in use (and the other will be otherCompoundButton) final CompoundButton compoundButton; final CompoundButton otherCompoundButton; if (mItemData.isExclusiveCheckable()) { if (mRadioButton == null) { insertRadioButton(); } compoundButton = mRadioButton; otherCompoundButton = mCheckBox; } else { if (mCheckBox == null) { insertCheckBox(); } compoundButton = mCheckBox; otherCompoundButton = mRadioButton; } if (checkable) { compoundButton.setChecked(mItemData.isChecked()); final int newVisibility = checkable ? VISIBLE : GONE; if (compoundButton.getVisibility() != newVisibility) { compoundButton.setVisibility(newVisibility); } // Make sure the other compound button isn't visible if (otherCompoundButton != null && otherCompoundButton.getVisibility() != GONE) { otherCompoundButton.setVisibility(GONE); } } else { if (mCheckBox != null) { mCheckBox.setVisibility(GONE); } if (mRadioButton != null) { mRadioButton.setVisibility(GONE); } } } public void setChecked(boolean checked) { CompoundButton compoundButton; if (mItemData.isExclusiveCheckable()) { if (mRadioButton == null) { insertRadioButton(); } compoundButton = mRadioButton; } else { if (mCheckBox == null) { insertCheckBox(); } compoundButton = mCheckBox; } compoundButton.setChecked(checked); } private void setSubMenuArrowVisible(boolean hasSubmenu) { if (mSubMenuArrowView != null) { mSubMenuArrowView.setVisibility(hasSubmenu ? View.VISIBLE : View.GONE); } } public void setShortcut(boolean showShortcut, char shortcutKey) { final int newVisibility = (showShortcut && mItemData.shouldShowShortcut()) ? VISIBLE : GONE; if (newVisibility == VISIBLE) { mShortcutView.setText(mItemData.getShortcutLabel()); } if (mShortcutView.getVisibility() != newVisibility) { mShortcutView.setVisibility(newVisibility); } } public void setIcon(Drawable icon) { final boolean showIcon = mItemData.shouldShowIcon() || mForceShowIcon; if (!showIcon && !mPreserveIconSpacing) { return; } if (mIconView == null && icon == null && !mPreserveIconSpacing) { return; } if (mIconView == null) { insertIconView(); } if (icon != null || mPreserveIconSpacing) { mIconView.setImageDrawable(showIcon ? icon : null); if (mIconView.getVisibility() != VISIBLE) { mIconView.setVisibility(VISIBLE); } } else { mIconView.setVisibility(GONE); } } @Override protected void onMeasure(int widthMeasureSpec, int heightMeasureSpec) { if (mIconView != null && mPreserveIconSpacing) { // Enforce minimum icon spacing ViewGroup.LayoutParams lp = getLayoutParams(); LayoutParams iconLp = (LayoutParams) mIconView.getLayoutParams(); if (lp.height > 0 && iconLp.width <= 0) { iconLp.width = lp.height; } } super.onMeasure(widthMeasureSpec, heightMeasureSpec); } private void insertIconView() { LayoutInflater inflater = getInflater(); mIconView = (ImageView) inflater.inflate(R.layout.abc_list_menu_item_icon, this, false); addView(mIconView, 0); } private void insertRadioButton() { LayoutInflater inflater = getInflater(); mRadioButton = (RadioButton) inflater.inflate(R.layout.abc_list_menu_item_radio, this, false); addView(mRadioButton); } private void insertCheckBox() { LayoutInflater inflater = getInflater(); mCheckBox = (CheckBox) inflater.inflate(R.layout.abc_list_menu_item_checkbox, this, false); addView(mCheckBox); } public boolean prefersCondensedTitle() { return false; } public boolean showsIcon() { return mForceShowIcon; } private LayoutInflater getInflater() { if (mInflater == null) { mInflater = LayoutInflater.from(getContext()); } return mInflater; } }