AndroidTextview跑马灯横向滚动

原理：自定义textview

源码：http://download.csdn.net/detail/lm_zp/9517135

xml

<RelativeLayout 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"
tools:context=".MainActivity" >

<com.bwie.androidtest.AutoText
android:id="@+id/autoTxt"
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:background="#ffffff"
android:textColor="#00ff00"
android:textSize="35sp" />

</RelativeLayout>

自定义textview

AutoText.java

package com.bwie.androidtest;

import android.content.Context;
import android.graphics.Canvas;
import android.graphics.Color;
import android.graphics.Paint;
import android.graphics.Paint.FontMetrics;
import android.graphics.Typeface;
import android.util.AttributeSet;
import android.util.DisplayMetrics;
import android.util.Log;
import android.view.WindowManager;
import android.widget.TextView;

public class AutoText extends TextView {

private int width, height;
private Paint paintText;
private float posx, posy;
private float speed = 0.0f;
private String text = "hello haha";
private float textWidth = 0;
private float moveDistance = 0.0f;
private boolean isStarting = false;

public AutoText(Context context) {
super(context);

}

public AutoText(Context context, AttributeSet attrs) {
super(context, attrs);

}

private void initView() {
paintText = new Paint();
//字体大小
paintText.setTextSize(50.0f);
//字体颜色
paintText.setColor(Color.BLACK);
paintText.setTypeface(Typeface.DEFAULT_BOLD);
paintText.setAntiAlias(true);
text = getText().toString();
textWidth = paintText.measureText(text);
Log.e("msg", "textWidth= " + textWidth);
this.speed = textWidth;
moveDistance = textWidth * 2 + width;
}

public void initDisplayMetrics(WindowManager windowManager) {
/* 取得屏幕分辨率大小 */
DisplayMetrics dm = new DisplayMetrics();
windowManager.getDefaultDisplay().getMetrics(dm);
this.width = dm.widthPixels;
this.height = dm.heightPixels;

initView();
this.posx = width + textWidth;
FontMetrics fm = paintText.getFontMetrics();
float baseline = fm.descent - fm.ascent;
//字体显示高度
this.posy = height / 2 - baseline;
}

public void startScroll() {
isStarting = true;
invalidate();
}

public void stopScroll() {
isStarting = false;
invalidate();
}

@Override
protected void onDraw(Canvas canvas) {
// super.onDraw(canvas);
canvas.drawText(text, posx - speed, posy, paintText);
if (!isStarting) {
return;
}
speed += 2.0f;
if (speed > moveDistance)
speed = textWidth;
invalidate();
}

}

MainActivity.java

package com.bwie.androidtest;

import android.os.Bundle;
import android.app.Activity;
import android.text.TextUtils.TruncateAt;
import android.view.Menu;
import android.widget.TextView;

public class MainActivity extends Activity {
String str11 = "促进青年教师全面发展，\n引导广大高校青年教师为实现中华民族伟大复兴的中国梦贡献力" + "\n"
+ "促进青年教师全面发展，\n引导广大高校青年教师为实现中华民族伟大复兴的中国梦贡献力" + "\n"
+ "  djsdnh   kshdfjks     \n\r\t ";

@Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
scroll3();
}

void scroll3() {
AutoText auto = (AutoText) findViewById(R.id.autoTxt);
auto.setText(str11);
//传递屏幕宽度
auto.initDisplayMetrics(getWindowManager());
//开始
auto.startScroll();
}

}