Question

我有不确定的进度条，当我从互联网上读取数据时显示。为了显示/消失进度条，我使用它的可见性。当我打开进度条选项时，我的应用程序从网络读取数据15分钟，当我删除进度条代码时，它持续20秒。它有可能使我的应用程序变得如此缓慢？

main_activity.xml：

<TableRow 
    android:gravity="center_horizontal"
    android:layout_marginTop="10dip"
    android:visibility="gone"
    android:id="@+id/progress_bar"
    >

    <ProgressBar
     android:layout_width="wrap_content" 
     android:layout_height="wrap_content"
     android:maxWidth="30dip"
     android:minWidth="30dip"
     android:maxHeight="30dip"
     android:minHeight="30dip"
     android:indeterminate="true"
     android:layout_gravity="center_horizontal"
     />
    <TextView
        android:layout_width="wrap_content" 
        android:layout_height="wrap_content"
        android:text="@string/searchingInProgress" 
        android:layout_gravity="center|center_horizontal"
        />

</TableRow>

第一个片段java代码（这通过执行类FindSongTask触发与net的连接，继承自ASyncTask）：

public void onCreate(Bundle savedInstanceState) {
    super.onCreate(savedInstanceState);
    setContentView(R.layout.activity_main);

    Button searchButton = (Button) findViewById(R.id.searchButton);

    searchButton.setOnClickListener(new OnClickListener() {

        @Override
        public void onClick(View v) {

            EditText searchQueryField = (EditText) findViewById(R.id.searchQueryField);
            String searchQuery = searchQueryField.getText().toString();

            if (searchQuery.length() > 0 && (currentQuery == null || !currentQuery.equals(searchQuery))) {
                new FindSongTask().execute(searchQuery);
                currentQuery = searchQuery;

                findViewById(R.id.progress_bar).setVisibility(View.VISIBLE);
                v.setEnabled(false);

            }

            InputMethodManager imm = (InputMethodManager)getSystemService(Context.INPUT_METHOD_SERVICE);
            imm.hideSoftInputFromWindow(searchQueryField.getWindowToken(), 0);



        }
    });

}

第二个片段（这是在连接到网络后执行的）：

instance.findViewById(R.id.searchButton).setEnabled(true);
findViewById(R.id.progress_bar).setVisibility(View.GONE);
super.onPostExecute(result);

Answer 1

尝试这样的事情......

public class MyActivity extends Activity{

    ProgressDialog pd;

    public void onCreate(Bundle savedInstanceState){
        super.onCreate(savedInstanceState);
        requestWindowFeature(Window.FEATURE_INDETERMINATE_PROGRESS);
        setContentView(R.layout.main);
    } 

    @Override
    public void onPause()
    {
            //don't leak a window
        super.onPause();
        if(pd != null)
            pd.dismiss();
    }

    //no networking allowed on main thread
    private class NetworkingTask extends AsyncTask<String,String,String>{
        int result;

        @Override
        protected void onPreExecute(){
            pd = ProgressDialog.show(Login.this,"","Display message...", true,false);
        }

        @Override
        protected String doInBackground(String...strings){
            //perform networking here
            return null;
        }

        @Override
        protected void onPostExecute(String unused){
            //check result
            pd.dismiss();
            Intent intent = new Intent(MyActivity.this,NextActivity.class);
            startActivity(intent);
        }
     }
}

android的性能问题与不确定的进度条

1 个答案: