TextSwitcher，ImageSwitcher切换器

TextSwitcher和ImageSwitcher可以用来实现文本或图片的切换功能。

这两个组件使用上基本类似，先来看TextSwitcher的使用。

<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" >

<TextSwitcher
android:id="@+id/switcher"
android:layout_width="match_parent"
android:layout_height="match_parent" >
</TextSwitcher>

</LinearLayout>

通过程序来动态建立切换器中显示文字的TextView。

public class MainActivity extends Activity {

private TextSwitcher switcher;

// 准备一组要显示的文字
private String[] allTexts = {
"Specialized ViewSwitcher that contains only children of type TextView. A TextSwitcher is useful to animate a label on screen. Whenever setText(CharSequence) is called, TextSwitcher animates the current text out and animates the new text in.Summary[Expand",
"]Inherited XML AttributesFrom class android.widget.ViewAnimatorFrom class android.widget.FrameLayoutFrom",
" class android.view.ViewGroupFrom class android.view.View[Expand]Inherited ConstantsFrom class android.",
"view.ViewGroupFrom class android.view.View[Expand]Inherited FieldsFrom class android.view.ViewPublic",
" ConstructorsTextSwitcher(Context context)Creates a new empty TextSwitcher.TextSwitcher(Context context",
", AttributeSet attrs)Creates a new empty TextSwitcher for the given context and with the specified set ",
"attributes.Public Methodsvoid	 addView(View child, int index, ViewGroup.LayoutParams params)Adds a child",
" view with the specified layout parameters.void	 onInitializeAccessibilityEvent(AccessibilityEvent " };

// 准备当前要显示的索引
private int index = 0;

// 保存按下时的坐标和时间
private float startX;
private long startTime;

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

Globals.init(this);

// 设置默认使用的布局文件
setContentView(R.layout.activity_main);

switcher = (TextSwitcher) findViewById(R.id.switcher);

// 设置建立TextView的工厂类
switcher.setFactory(new ViewFactory() {

@Override
public View makeView() {
// 建立要显示文字的TextView
TextView text = new TextView(MainActivity.this);
text.setTextColor(Color.BLACK);
text.setBackgroundColor(Color.WHITE);
text.setTextSize(16);
text.setLayoutParams(new LayoutParams(
LayoutParams.MATCH_PARENT, LayoutParams.MATCH_PARENT));

return text;
}
});

// 处理内容
switcher.setText(allTexts[index]);

// 设置动画效果, 系统动画功能不完善,一般都满足不了开发的需求, 因此这里完成一个自定义的平移动画
// switcher.setInAnimation(AnimationUtils.loadAnimation(this,
// android.R.anim.slide_in_left));
// switcher.setOutAnimation(AnimationUtils.loadAnimation(this,
// android.R.anim.slide_out_right));

// 加入触屏监听, 使用该监听的前提是, 组件必须先加入过OnClickListener
switcher.setOnClickListener(new OnClickListener() {
@Override
public void onClick(View v) {
}
});

switcher.setOnTouchListener(new OnTouchListener() {
@Override
public boolean onTouch(View v, MotionEvent event) {
// 只支持单点操作
if (event.getPointerCount() == 1) {
if (event.getAction() == MotionEvent.ACTION_DOWN) {
// 手指刚按到屏幕上
startX = event.getX();
startTime = System.currentTimeMillis();
} else if (event.getAction() == MotionEvent.ACTION_MOVE) {
// 手指在屏幕上滑动
} else if (event.getAction() == MotionEvent.ACTION_UP) {
// 手指从屏幕上离开
// 先判断时间是否合法, 要求在1秒内完成滑动的动作
if (System.currentTimeMillis() - startTime < 1000) {
// 判断当前的横坐标
if (startX - event.getX() >= 50) {
// 下一页
if (index < allTexts.length - 1) {
index++;

Animation inAnim = new TranslateAnimation(
Globals.SCREEN_WIDTH + 10, 0, 0, 0);
Animation outAnim = new TranslateAnimation(
0, -Globals.SCREEN_WIDTH - 10, 0, 0);

// 设置动画持续时间
inAnim.setDuration(1000);
outAnim.setDuration(1000);

switcher.setInAnimation(inAnim);
switcher.setOutAnimation(outAnim);

switcher.setText(allTexts[index]);

}
} else if (event.getX() - startX >= 50) {
// 上一页
if (index > 0) {
index--;

Animation inAnim = new TranslateAnimation(
-Globals.SCREEN_WIDTH - 10, 0, 0, 0);
Animation outAnim = new TranslateAnimation(
0, Globals.SCREEN_WIDTH + 10, 0, 0);
// 设置动画持续时间
inAnim.setDuration(1000);
outAnim.setDuration(1000);

switcher.setInAnimation(inAnim);
switcher.setOutAnimation(outAnim);

switcher.setText(allTexts[index]);
}
}
}
}
} else {
Toast.makeText(MainActivity.this, "只支持单点操作",
Toast.LENGTH_SHORT).show();
}

return false;
}
});

}
}

如果想改为ImageSwitcher，只需要将设置的内容变为图片，建立的组件变为ImageView即可。