本文实例讲述了Android编程实现Toast只显示最后一条的方法。分享给大家供大家参考，具体如下：
在做Android开发中，时不时的可能会用到Toast，但用Toast的时候，连续使用会存在一个问题，就是一条条显示Toast。而不是直接显示最后一条。因此，根据此需求，现在写了ToastUtil这个类，该类中有三个方法供选择。
ToastUtil.Java
import android.content.Context;
import android.graphics.PixelFormat;
import android.os.Handler;
import android.os.Looper;
import android.os.Message;
import android.view.Gravity;
import android.view.WindowManager;
import android.widget.TextView;
import android.widget.Toast;
public class ToastUtil {
//方法一 private static Handler mHandler = new Handler(Looper.getMainLooper());
private static Toast mToast = null;
private static Object synObject = new Object();
public static void showToastByThread(Context context, String msg){
showToastByThread(context, msg, Toast.LENGTH_SHORT);
}
public static void showToastByThread(Context context, int msg){
showToastByThread(context, context.getText(msg), Toast.LENGTH_SHORT);
}
public static void showToastByThread(final Context context, final CharSequence msg, final int length){
new Thread(new Runnable() {
@Override public void run() {
mHandler.post(new Runnable() {
@Override public void run() {
synchronized (synObject) {
if (mToast != null){
mToast.setText(msg);
mToast.setDuration(length);
}
else{
mToast = Toast.makeText(context, msg, length);
}
mToast.show();
}
}
}
);
}
}
).start();
}
//方法二:注意此方法不能再子线程中使用 private static long oneTime;
private static long twoTime;
private static String oldMsg;
public static void showToastByTime(Context context, String msg){
if (mToast == null) {
mToast = Toast.makeText(context, msg, Toast.LENGTH_SHORT);
mToast.show();
oneTime = System.currentTimeMillis();
}
else {
twoTime = System.currentTimeMillis();
if (msg.equals(oldMsg)){
if (twoTime-oneTime > Toast.LENGTH_SHORT){
mToast.show();
}
}
else {
oldMsg = msg;
mToast.setText(msg);
mToast.show();
}
}
oneTime = twoTime;
}
public static void showToastByTime(Context context, int msg){
showToastByTime(context, context.getString(msg));
}
//方法三 public static TextView mTextView;
public static WindowManager mWindowManager = null;
private static Handler mPriHandler = new Handler(){
@Override public void handleMessage(Message msg) {
cancelToast();
}
}
;
public static void showToastByWindow(Context context, String msg){
mWindowManager = (WindowManager) context.getSystemService(Context.WINDOW_SERVICE);
if (mTextView == null){
mTextView = new TextView(context);
}
mTextView.setText(msg);
mTextView.setTextSize(20);
mTextView.setPadding(0, 0, 0, 30);
if (mTextView.getParent() == null){
WindowManager.LayoutParams params = new WindowManager.LayoutParams();
params.gravity= Gravity.BOTTOM;
params.alpha = 0.65f;
params.x = 0;
params.height = WindowManager.LayoutParams.WRAP_CONTENT;
params.width = WindowManager.LayoutParams.WRAP_CONTENT;
params.flags = WindowManager.LayoutParams.FLAG_NOT_FOCUSABLE | WindowManager.LayoutParams.FLAG_NOT_TOUCHABLE | WindowManager.LayoutParams.FLAG_KEEP_SCREEN_ON | WindowManager.LayoutParams.FLAG_LAYOUT_IN_SCREEN;
params.format = PixelFormat.TRANSLUCENT;
params.windowAnimations = 0;
mWindowManager.addView(mTextView, params);
mPriHandler.sendEmptyMessageDelayed(101, 1000);
}
else {
mTextView.setText(msg);
mPriHandler.removeMessages(101);
mPriHandler.sendEmptyMessageDelayed(101, 1000);
}
}
public static void cancelToast(){
if (mTextView != null && mTextView.getParent() != null){
mWindowManager.removeView(mTextView);
}
}
}
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希望本文所述对大家Android程序设计有所帮助。
