ZoomControls 缩放控制

ZoomControls是控制组件的大小，是LinearLayout的子类。有放大和缩小两个方法 setOnZoomInClickListener和setOnZoomOutClickListener。

主程序如下

package com.jackie.zoomcontrolsproject;

import android.app.Activity;

import android.os.Bundle;

import android.view.Menu;

import android.view.View;

import android.view.View.OnClickListener;

import android.widget.TextView;

import android.widget.ZoomControls;

public class MyDemo extends Activity {
private ZoomControls zoomControls = null;
private TextView show = null;
private int size = 10;

@Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
super.setContentView(R.layout.main);
this.show = (TextView) super.findViewById(R.id.show);

this.zoomControls = (ZoomControls) super
.findViewById(R.id.zoomControls);
this.zoomControls
.setOnZoomInClickListener(new OnZoomInClickListenerImpl());
this.zoomControls
.setOnZoomOutClickListener(new OnZoomOutClickListenerImpl());
}

private class OnZoomInClickListenerImpl implements OnClickListener {

@Override
public void onClick(View arg0) {
MyDemo.this.size = size + 2;
MyDemo.this.show.setTextSize(size);
}

}
private class OnZoomOutClickListenerImpl implements OnClickListener {

@Override
public void onClick(View arg0) {
MyDemo.this.size = size - 2;
MyDemo.this.show.setTextSize(size);
}

}

}

布局文件

<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"

    xmlns:tools="http://schemas.android.com/tools"

    android:layout_width="match_parent"

    android:layout_height="match_parent"

    android:orientation="vertical"

    tools:context=".MyDemo" >

    <TextView

        android:id="@+id/show"

        android:layout_width="wrap_content"

        android:layout_height="wrap_content"

        android:text="深圳南山(Shenzhen)"

        android:textSize="10px" />

    <ZoomControls 

        android:id="@+id/zoomControls"

        android:layout_width="wrap_content"

        android:layout_height="wrap_content"

        android:gravity="bottom"/>

</LinearLayout>