Android example source code file (BigCache.java)

This example Android source code file (BigCache.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, bigcache, display, linearlayout, os, override, scrollview, ui, view, widget

The BigCache.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 android.view;

import com.android.frameworks.coretests.R;

import android.os.Bundle;
import android.app.Activity;
import android.widget.LinearLayout;
import android.widget.ScrollView;
import android.view.ViewGroup;
import android.view.View;
import android.view.Display;
import android.view.ViewConfiguration;

/**
 * This activity contains two Views, one as big as the screen, one much larger. The large one
 * should not be able to activate its drawing cache.
 */
public class BigCache extends Activity {
    @Override
    protected void onCreate(Bundle icicle) {
        super.onCreate(icicle);

        final LinearLayout testBed = new LinearLayout(this);
        testBed.setOrientation(LinearLayout.VERTICAL);
        testBed.setLayoutParams(new ViewGroup.LayoutParams(
                ViewGroup.LayoutParams.MATCH_PARENT, ViewGroup.LayoutParams.WRAP_CONTENT));

        final int cacheSize = ViewConfiguration.getMaximumDrawingCacheSize();
        final Display display = getWindowManager().getDefaultDisplay();
        final int screenWidth = display.getWidth();
        final int screenHeight = display.getHeight();

        final View tiny = new View(this);
        tiny.setId(R.id.a);
        tiny.setBackgroundColor(0xFFFF0000);
        tiny.setLayoutParams(new LinearLayout.LayoutParams(screenWidth, screenHeight));

        final View large = new View(this);
        large.setId(R.id.b);
        large.setBackgroundColor(0xFF00FF00);
        // Compute the height of the view assuming a cache size based on ARGB8888
        final int height = 2 * (cacheSize / 2) / screenWidth;
        large.setLayoutParams(new LinearLayout.LayoutParams(screenWidth, height));

        final ScrollView scroller = new ScrollView(this);
        scroller.setLayoutParams(new ViewGroup.LayoutParams(
                ViewGroup.LayoutParams.MATCH_PARENT, ViewGroup.LayoutParams.MATCH_PARENT));

        testBed.addView(tiny);
        testBed.addView(large);
        scroller.addView(testBed);

        setContentView(scroller);
    }
}