Question

在系统中，当我选择msg默认情况下，msg显示在spinner上。我需要这个项目那些选择项目只显示spinner。如果我更改项目不显示前一个选择项目显示在微调器上。的 list.java

Spinner sp1;
TextView entry;
@Override
protected void onCreate(Bundle savedInstanceState) {
    super.onCreate(savedInstanceState);
    setContentView(R.layout.list);
    sp1=(Spinner) findViewById(R.id.spinner1);
    entry = (TextView)findViewById(R.id.TextView123);
    getFilesnames();        
}
private void getFilesnames() {
    // TODO Auto-generated method stub
    String[] filenames=getApplicationContext().fileList();
    List<String> list=new ArrayList<String>();
    for(int i=0;i<filenames.length;i++){
        list.add(filenames[i]);

    }
    ArrayAdapter<String> filenameAdapter=new ArrayAdapter<String>(this,android.R.layout.simple_spinner_item,list);
    sp1.setAdapter(filenameAdapter);
}
public void onClick(View v) {
    // TODO Auto-generated method stub
    String selectFile = String.valueOf(sp1.getSelectedItem());
    openFile(selectFile);
}


private void openFile(String selectFile) {
    // TODO Auto-generated method stub
    String value = "";
    FileInputStream fis;

    try {
        fis = openFileInput(selectFile);
        byte[] input = new byte[fis.available()];
        while(fis.read(input) != -1){
            value += new String(input);
        }
        fis.close();
    } catch (FileNotFoundException e) {
        // TODO Auto-generated catch block
        e.printStackTrace();
    } catch (IOException e) {
        // TODO Auto-generated catch block
        e.printStackTrace();
    }
    entry.setText(value);

}

Answer 1

检查绑定后list是否有值，如下面的代码：

private void getFilesnames() {
    // TODO Auto-generated method stub
    String[] filenames=getApplicationContext().fileList();
    List<String> list=new ArrayList<String>();
    for(int i=0;i<filenames.length;i++){
        list.add(filenames[i]);

    }
    /***
     check here list has value or not
     ***/

    if(list.size() <= 0) {
       list.add("You string.....");
    }

    ArrayAdapter<String> filenameAdapter=new ArrayAdapter<String>(this,android.R.layout.simple_spinner_item,list);
    sp1.setAdapter(filenameAdapter);
}

如何选择收件箱msg默认显示在微调器上

1 个答案: