Question

我有布局主要活动和另一个列表活动。但是，当我尝试呼叫列表活动时，我正在崩溃。请帮我开始列表活动（注意：列表活动有EditText和按钮，用于将文本添加到列表活动中的现有列表视图）我只想添加listactivity中已经存在的文本列表视图。非常感谢!!

公共类MainActivity扩展了Activity {

@Override
protected void onCreate(Bundle savedInstanceState) {
    super.onCreate(savedInstanceState);
    setContentView(R.layout.activity_main);
}

public void onClick(View view){

    EditText txt=(EditText)findViewById(R.id.txtPass);
    if (txt.getText().length()==0){
        Toast.makeText(this, "Please enter password to continue!!", Toast.LENGTH_SHORT).show();
        txt.getText().clear();
        return;
    }

    if(txt.getText().toString().contains("Test")){
        Button btn;
        btn=(Button)findViewById(R.id.btnSubmit);
        Intent intent=new Intent(this,Passwordlist.class);
        startActivity(intent);
    }

}

Answer 1

首先，对代码进行一些更改：

    Button btn;
    EditText txt

    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_main);

        //Do this stuff here and not in onClick. Your views should be defined in //onCreate() and before the onCLick() 
        txt=(EditText)findViewById(R.id.txtPass);
        btn=(Button)findViewById(R.id.btnSubmit);
    }

    public void onClick(View view){

        Intent intent=new Intent(YourActivity.this,Passwordlist.class);

        if (txt.getText().toString().matches("")){
            Toast.makeText(this, "Please enter password to continue!!", Toast.LENGTH_SHORT).show();
            txt.getText().clear();
        }

        else if(txt.getText().toString().contains("Test")){

            startActivity(intent);
        }

    }

看看是否有效。

android从活动类调用ListActivity

1 个答案: