Android example source code file (RequestRectangleVisible.java)

This example Android source code file (RequestRectangleVisible.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, drawing, os, override, rect, requestrectanglevisible, textview, ui, view, widget

The RequestRectangleVisible.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.widget.scroll;

import com.android.frameworks.coretests.R;

import android.app.Activity;
import android.os.Bundle;
import android.graphics.Rect;
import android.view.View;
import android.widget.ScrollView;
import android.widget.TextView;

/**
 * A screen with some scenarios that exercise {@link ScrollView}'s implementation
 * of {@link android.view.ViewGroup#requestChildRectangleOnScreen}:
 * <li>Scrolling to something off screen (from top and from bottom)
 * <li>Scrolling to bring something that is larger than the screen on screen
 *  (from top and from bottom).
 */
public class RequestRectangleVisible extends Activity {

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

        setContentView(R.layout.scroll_to_rectangle);

        final Rect rect = new Rect();
        final View childToMakeVisible = findViewById(R.id.childToMakeVisible);

        final TextView topBlob = (TextView) findViewById(R.id.topBlob);
        final TextView bottomBlob = (TextView) findViewById(R.id.bottomBlob);

        // estimate to get blobs larger than screen
        int screenHeight = getWindowManager().getDefaultDisplay().getHeight();
        int numLinesForScreen = screenHeight / 18;

        for (int i = 0; i < numLinesForScreen; i++) {
            topBlob.append(i + " another line in the blob\n");
            bottomBlob.append(i + " another line in the blob\n");
        }

        findViewById(R.id.scrollToRectFromTop).setOnClickListener(new View.OnClickListener() {

            public void onClick(View v) {
                rect.set(0, 0, childToMakeVisible.getLeft(), childToMakeVisible.getHeight());
                childToMakeVisible.requestRectangleOnScreen(rect, true);
            }
        });

        findViewById(R.id.scrollToRectFromTop2).setOnClickListener(new View.OnClickListener() {

            public void onClick(View v) {
                rect.set(0, 0, topBlob.getWidth(), topBlob.getHeight());
                topBlob.requestRectangleOnScreen(rect, true);
            }
        });

        findViewById(R.id.scrollToRectFromBottom).setOnClickListener(new View.OnClickListener() {

            public void onClick(View v) {
                rect.set(0, 0, childToMakeVisible.getLeft(), childToMakeVisible.getHeight());
                childToMakeVisible.requestRectangleOnScreen(rect, true);
            }
        });

        findViewById(R.id.scrollToRectFromBottom2).setOnClickListener(new View.OnClickListener() {

            public void onClick(View v) {
                rect.set(0, 0, bottomBlob.getWidth(), bottomBlob.getHeight());
                bottomBlob.requestRectangleOnScreen(rect, true);
            }
        });
        
    }



}