Question

我很难找到解决这种情况的方法。我需要帮助，如果我的字段没有使用textwatcher填充，我试图禁用发送按钮。以下是代码的一部分：

public class Main5Activity extends AppCompatActivity {

    TextView shoppinglist, fullname;

    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_main5);

        fullname = (TextView) findViewById(R.id.fullname);
        shoppinglist = (TextView) findViewById(R.id.shoppinglist);

    public void send(View v) {

        new Send().execute();
    }
}

Answer 1

试试这个，并使用EditText，TextView不可输入：

editText1.addTextChangedListener(this); imageButton.setEnable(false);

@Override
public void afterTextChanged(Editable s) {
    if (s.toString().equals("")) {
        imageButton.setEnabled(false);
    } else {
        imageButton.setEnabled(true);
    }
}

Answer 2

实际上，您不需要使用textwatcher来禁用发送按钮。您所能做的就是在if循环中禁用onCreate方法中的发送按钮。

注意：使用EditText而不是TextView来获取用户的输入。

    public class Main5Activity extends AppCompatActivity {

    EditText shoppinglist, fullname;

    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_main5);
    fullname = findViewById(R.id.fullname);
    button1 = (Button) findViewById(R.id.buttsave);
    shoppinglist = findViewById(R.id.shoppinglist);
    final String username = fullname.getText().toString();
        final String shopList = shoppinglist.getText().toString();

        if (TextUtils.isEmpty(username)&&TextUtils.isEmpty(shopList)) {
            fullname.setError("Please enter your fullname");
            shoppinglist.setError("Please select shopping list");
            button1.setEnabled(false);
        }
       else {
       button1.setEnabled(true);
       }


//close onCreate here
}

public void send(View v) {
 // it is not possible to enable the send button here because you are already 
// executing the send method. So it should have already been enabled.       
        new Send().execute();
    }

同样，如果有必要使用textwatcher，请执行以下操作：

public class Main5Activity extends AppCompatActivity implements TextWatcher {

    EditText shoppinglist, fullname;

    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_main5);

        fullname = findViewById(R.id.fullname);
        button1 = (Button) findViewById(R.id.buttsave);
        shoppinglist = findViewById(R.id.shoppinglist);
        fullname.addTextChangedListener(this);
        shoppinglist.addTextChangedListener(this);
}

@Override
    public void beforeTextChanged(CharSequence s, int start, int count, int after) {

    }

    @Override
    public void onTextChanged(CharSequence s, int start, int before, int count) {

    }

    @Override
    public void afterTextChanged(Editable s) {
    final String username = fullname.getText().toString();
            final String shopList = shoppinglist.getText().toString();

            if (TextUtils.isEmpty(username)&&TextUtils.isEmpty(shopList)) {
                fullname.setError("Please enter your fullname");
                shoppinglist.setError("Please select shopping list");
                button1.setEnabled(false);
            }
           else {
           button1.setEnabled(true);
           }
    }

    public void send(View v) {
        button1.setEnabled(true);
        new Send().execute();
    }

希望这会有所帮助。如果您仍有任何疑问，请在评论中回复。

如果我的字段未使用textwatcher填充，如何禁用发送按钮？

2 个答案: