Android example source code file (InternalSelectionFocus.java)

This example Android source code file (InternalSelectionFocus.java) is included in the DevDaily.com "Java Source Code Warehouse" project. The intent of this project is to help you "Learn Android by Example" ^TM.

Java - Android tags/keywords

activity, android, app, application, internalselectionfocus, internalselectionview, linearlayout, os, override, ui, view, widget

The InternalSelectionFocus.java Android example source code

/*
 * Copyright (C) 2007 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 com.example.android.apis.view;

import android.app.Activity;
import android.os.Bundle;
import android.view.ViewGroup;
import android.widget.LinearLayout;

/**
 * {@link android.view.View#requestFocus(int, android.graphics.Rect)}
 * and
 * {@link android.view.View#onFocusChanged(boolean, int, android.graphics.Rect)}
 * work together to give a newly focused item a hint about the most interesting
 * rectangle of the previously focused view.  The view taking focus can use this
 * to set an internal selection more appropriate using this rect.
 *
 * This Activity excercises that behavior using three adjacent {@link InternalSelectionView}
 * that report interesting rects when giving up focus, and use interesting rects
 * when taking focus to best select the internal row to show as selected.
 *
 * Were {@link InternalSelectionView} not to override {@link android.view.View#getFocusedRect}, or
 * {@link android.view.View#onFocusChanged(boolean, int, android.graphics.Rect)}, the focus would
 * jump to some default internal selection (the top) and not allow for the smooth handoff.
 */
public class InternalSelectionFocus extends Activity {

    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);

        final LinearLayout layout = new LinearLayout(this);
        layout.setOrientation(LinearLayout.HORIZONTAL);
        layout.setLayoutParams(new ViewGroup.LayoutParams(
                ViewGroup.LayoutParams.FILL_PARENT,
                ViewGroup.LayoutParams.FILL_PARENT));

        LinearLayout.LayoutParams params = new LinearLayout.LayoutParams(0,
                ViewGroup.LayoutParams.FILL_PARENT, 1);

        final InternalSelectionView leftColumn = new InternalSelectionView(this, 5, "left column");
        leftColumn.setLayoutParams(params);
        leftColumn.setPadding(10, 10, 10, 10);
        layout.addView(leftColumn);

        final InternalSelectionView middleColumn = new InternalSelectionView(this, 5, "middle column");
        middleColumn.setLayoutParams(params);
        middleColumn.setPadding(10, 10, 10, 10);
        layout.addView(middleColumn);

        final InternalSelectionView rightColumn = new InternalSelectionView(this, 5, "right column");
        rightColumn.setLayoutParams(params);
        rightColumn.setPadding(10, 10, 10, 10);
        layout.addView(rightColumn);

        setContentView(layout);
    }


}