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/* * 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.widget; import android.content.Context; import android.content.res.TypedArray; import android.util.AttributeSet; import android.view.View; import android.view.ViewGroup; import android.widget.RemoteViews.RemoteView; /** * A layout that lets you specify exact locations (x/y coordinates) of its * children. Absolute layouts are less flexible and harder to maintain than * other types of layouts without absolute positioning. * * <p><strong>XML attributes</strong></p> <p> See {@link * android.R.styleable#ViewGroup ViewGroup Attributes}, {@link * android.R.styleable#View View Attributes}</p> * * @deprecated Use {@link android.widget.FrameLayout}, {@link android.widget.RelativeLayout} * or a custom layout instead. */ @Deprecated @RemoteView public class AbsoluteLayout extends ViewGroup { public AbsoluteLayout(Context context) { this(context, null); } public AbsoluteLayout(Context context, AttributeSet attrs) { this(context, attrs, 0); } public AbsoluteLayout(Context context, AttributeSet attrs, int defStyleAttr) { this(context, attrs, defStyleAttr, 0); } public AbsoluteLayout(Context context, AttributeSet attrs, int defStyleAttr, int defStyleRes) { super(context, attrs, defStyleAttr, defStyleRes); } @Override protected void onMeasure(int widthMeasureSpec, int heightMeasureSpec) { int count = getChildCount(); int maxHeight = 0; int maxWidth = 0; // Find out how big everyone wants to be measureChildren(widthMeasureSpec, heightMeasureSpec); // Find rightmost and bottom-most child for (int i = 0; i < count; i++) { View child = getChildAt(i); if (child.getVisibility() != GONE) { int childRight; int childBottom; AbsoluteLayout.LayoutParams lp = (AbsoluteLayout.LayoutParams) child.getLayoutParams(); childRight = lp.x + child.getMeasuredWidth(); childBottom = lp.y + child.getMeasuredHeight(); maxWidth = Math.max(maxWidth, childRight); maxHeight = Math.max(maxHeight, childBottom); } } // Account for padding too maxWidth += mPaddingLeft + mPaddingRight; maxHeight += mPaddingTop + mPaddingBottom; // Check against minimum height and width maxHeight = Math.max(maxHeight, getSuggestedMinimumHeight()); maxWidth = Math.max(maxWidth, getSuggestedMinimumWidth()); setMeasuredDimension(resolveSizeAndState(maxWidth, widthMeasureSpec, 0), resolveSizeAndState(maxHeight, heightMeasureSpec, 0)); } /** * Returns a set of layout parameters with a width of * {@link android.view.ViewGroup.LayoutParams#WRAP_CONTENT}, * a height of {@link android.view.ViewGroup.LayoutParams#WRAP_CONTENT} * and with the coordinates (0, 0). */ @Override protected ViewGroup.LayoutParams generateDefaultLayoutParams() { return new LayoutParams(LayoutParams.WRAP_CONTENT, LayoutParams.WRAP_CONTENT, 0, 0); } @Override protected void onLayout(boolean changed, int l, int t, int r, int b) { int count = getChildCount(); for (int i = 0; i < count; i++) { View child = getChildAt(i); if (child.getVisibility() != GONE) { AbsoluteLayout.LayoutParams lp = (AbsoluteLayout.LayoutParams) child.getLayoutParams(); int childLeft = mPaddingLeft + lp.x; int childTop = mPaddingTop + lp.y; child.layout(childLeft, childTop, childLeft + child.getMeasuredWidth(), childTop + child.getMeasuredHeight()); } } } @Override public ViewGroup.LayoutParams generateLayoutParams(AttributeSet attrs) { return new AbsoluteLayout.LayoutParams(getContext(), attrs); } // Override to allow type-checking of LayoutParams. @Override protected boolean checkLayoutParams(ViewGroup.LayoutParams p) { return p instanceof AbsoluteLayout.LayoutParams; } @Override protected ViewGroup.LayoutParams generateLayoutParams(ViewGroup.LayoutParams p) { return new LayoutParams(p); } @Override public boolean shouldDelayChildPressedState() { return false; } /** * Per-child layout information associated with AbsoluteLayout. * See * {@link android.R.styleable#AbsoluteLayout_Layout Absolute Layout Attributes} * for a list of all child view attributes that this class supports. */ public static class LayoutParams extends ViewGroup.LayoutParams { /** * The horizontal, or X, location of the child within the view group. */ public int x; /** * The vertical, or Y, location of the child within the view group. */ public int y; /** * Creates a new set of layout parameters with the specified width, * height and location. * * @param width the width, either {@link #MATCH_PARENT}, {@link #WRAP_CONTENT} or a fixed size in pixels * @param height the height, either {@link #MATCH_PARENT}, {@link #WRAP_CONTENT} or a fixed size in pixels * @param x the X location of the child * @param y the Y location of the child */ public LayoutParams(int width, int height, int x, int y) { super(width, height); this.x = x; this.y = y; } /** * Creates a new set of layout parameters. The values are extracted from * the supplied attributes set and context. The XML attributes mapped * to this set of layout parameters are: * * <ul> * <li><code>layout_x</code>: the X location of the child</li> * <li><code>layout_y</code>: the Y location of the child</li> * <li>All the XML attributes from * {@link android.view.ViewGroup.LayoutParams}</li> * </ul> * * @param c the application environment * @param attrs the set of attributes from which to extract the layout * parameters values */ public LayoutParams(Context c, AttributeSet attrs) { super(c, attrs); TypedArray a = c.obtainStyledAttributes(attrs, com.android.internal.R.styleable.AbsoluteLayout_Layout); x = a.getDimensionPixelOffset(com.android.internal.R.styleable.AbsoluteLayout_Layout_layout_x, 0); y = a.getDimensionPixelOffset(com.android.internal.R.styleable.AbsoluteLayout_Layout_layout_y, 0); a.recycle(); } /** * {@inheritDoc} */ public LayoutParams(ViewGroup.LayoutParams source) { super(source); } @Override public String debug(String output) { return output + "Absolute.LayoutParams={width=" + sizeToString(width) + ", height=" + sizeToString(height) + " x=" + x + " y=" + y + "}"; } } }