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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.annotation.NonNull;
import android.content.Context;
import android.view.Gravity;
import android.view.View;
import android.view.ViewDebug;
import android.view.ViewGroup;
import java.util.ArrayList;
/**
* FrameLayout is designed to block out an area on the screen to display
* a single item. Generally, FrameLayout should be used to hold a single child view, because it can
* be difficult to organize child views in a way that's scalable to different screen sizes without
* the children overlapping each other. You can, however, add multiple children to a FrameLayout
* and control their position within the FrameLayout by assigning gravity to each child, using the
* {@code
* android:layout_gravity} attribute.
* Child views are drawn in a stack, with the most recently added child on top.
* The size of the FrameLayout is the size of its largest child (plus padding), visible
* or not (if the FrameLayout's parent permits). Views that are {@link android.view.View#GONE} are
* used for sizing
* only if {@link #setMeasureAllChildren(boolean) setConsiderGoneChildrenWhenMeasuring()}
* is set to true.
*
* @attr ref android.R.styleable#FrameLayout_measureAllChildren
*/
public class FrameLayout extends ViewGroup {
private static final int DEFAULT_CHILD_GRAVITY = Gravity.TOP | Gravity.START;
@ViewDebug.ExportedProperty(category = "measurement")
boolean mMeasureAllChildren = false;
@ViewDebug.ExportedProperty(category = "padding")
private int mForegroundPaddingLeft = 0;
@ViewDebug.ExportedProperty(category = "padding")
private int mForegroundPaddingTop = 0;
@ViewDebug.ExportedProperty(category = "padding")
private int mForegroundPaddingRight = 0;
@ViewDebug.ExportedProperty(category = "padding")
private int mForegroundPaddingBottom = 0;
private final ArrayList mMatchParentChildren = new ArrayList<>(1);
public FrameLayout(@NonNull Context context) {
//super(context);
}
/**
* Per-child layout information for layouts that support margins.
* See {@link android.R.styleable#FrameLayout_Layout FrameLayout Layout Attributes}
* for a list of all child view attributes that this class supports.
*
* @attr ref android.R.styleable#FrameLayout_Layout_layout_gravity
*/
public static class LayoutParams {
/**
* Value for {@link #gravity} indicating that a gravity has not been
* explicitly specified.
*/
public static final int UNSPECIFIED_GRAVITY = -1;
/**
* The gravity to apply with the View to which these layout parameters
* are associated.
*
* The default value is {@link #UNSPECIFIED_GRAVITY}, which is treated
* by FrameLayout as {@code Gravity.TOP | Gravity.START}.
*
* @see android.view.Gravity
* @attr ref android.R.styleable#FrameLayout_Layout_layout_gravity
*/
public int gravity = UNSPECIFIED_GRAVITY;
public LayoutParams(int width, int height) {
//super(width, height);
}
/**
* Creates a new set of layout parameters with the specified width, height
* and weight.
*
* @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 gravity the gravity
*
* @see android.view.Gravity
*/
public LayoutParams(int width, int height, int gravity) {
//super(width, height);
this.gravity = gravity;
}
public LayoutParams(@NonNull ViewGroup.LayoutParams source) {
//super(source);
}
/**
* Copy constructor. Clones the width, height, margin values, and
* gravity of the source.
*
* @param source The layout params to copy from.
*/
public LayoutParams(@NonNull LayoutParams source) {
//super(source);
this.gravity = source.gravity;
}
}
}