转载请标明出处：http://77blogs.com/?p=138
利用Activity.runOnUiThread(Runnable)把更新ui的代码创建在Runnable中，然后在需要更新ui时，把这个Runnable对象传给Activity.runOnUiThread(Runnable).
Runnable对像就能在ui程序中被调用。
|
1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 |
/** * Runs the specified action on the UI thread. If the current thread is the UI * thread, then the action is executed immediately. If the current thread is * not the UI thread, the action is posted to the event queue of the UI thread. * * @param action the action to run on the UI thread */ public final void runOnUiThread(Runnable action) { if (Thread.currentThread() != mUiThread) { mHandler.post(action); } else { action.run(); } } |
从上面的源代码中可以看出，程序首先会判断当前线程是否是UI线程，如果是就直接运行，如果不是则post，这时其实质还是使用的Handler机制来处理线程与UI通讯。
|
1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 |
private ProgressDialog progressDialog; Context mContext； progressDialog = new ProgressDialog(mContext); String stri = mContext.getResources().getString(R.string.Is_sending_a_request); progressDialog.setMessage(stri); progressDialog.setCanceledOnTouchOutside(false); progressDialog.show(); new Thread(new Runnable() { public void run() { try { ((Activity)mContext).runOnUiThread(new Runnable() { public void run() { progressDialog.dismiss(); String s1 = mContext.getResources().getString(R.string.send_successful); Toast.makeText(mContext, s1, Toast.LENGTH_LONG).show(); } }); } catch (final Exception e) { ((Activity)mContext).runOnUiThread(new Runnable() { public void run() { progressDialog.dismiss(); String s2 = mContext.getResources().getString(R.string.Request_add_buddy_failure); Toast.makeText(mContext, s2 + e.getMessage(), Toast.LENGTH_LONG).show(); } }); } } }).start(); |
用这种方式创建ProgressDialog就比较方便，或者刷新adapter也比使用Thread+Handler方便。
如果不是在activity中创建，需要在前面加上((Activity)mContext). 。
