android沙漏

Question

如何在Android应用程序中以编程方式显示沙漏？

Answer 1

您可以使用ProgressDialog：

ProgressDialog dialog = new ProgressDialog(this);
dialog.setMessage("Thinking...");
dialog.setIndeterminate(true);
dialog.setCancelable(false);
dialog.show();

上面的代码会在Activity：

之上显示以下对话框

或者（或另外），您可以在Activity的标题栏中显示进度指示器。

onCreate()使用以下代码Activity方法顶部附近need to request this as a feature：

requestWindowFeature(Window.FEATURE_INDETERMINATE_PROGRESS);

然后像这样打开它：

setProgressBarIndeterminateVisibility(true);

然后将其关闭：

setProgressBarIndeterminateVisibility(false);

Answer 2

以下是使用AsyncTask执行此操作的简单示例：

public class MyActivity extends Activity {

    protected void onCreate(Bundle savedInstanceState) {

        ...

        new MyLoadTask(this).execute(); //If you have parameters you can pass them inside execute method

    }

    private class MyLoadTask extends AsyncTask <Object,Void,String>{        

        private ProgressDialog dialog;

        public MyLoadTask(MyActivity act) {
            dialog = new ProgressDialog(act);
        }       

        protected void onPreExecute() {
            dialog.setMessage("Loading...");
            dialog.show();
        }       

        @Override
        protected String doInBackground(Object... params) {         
            //Perform your task here.... 
            //Return value ... you can return any Object, I used String in this case

            try {
                Thread.sleep(6000);
            } catch (InterruptedException e) {
                e.printStackTrace();
            }
            return(new String("test"));
        }

        @Override
        protected void onPostExecute(String str) {          
            //Update your UI here.... Get value from doInBackground ....
            if (dialog.isShowing()) {
                dialog.dismiss();
            }           
        }
    }