How to disable Button if EditText is empty ?

Question

I have an EditText and a Button in my application.

When the button is clicked,the text entered in the EditText is added to a ListView.

I want to disable the Button if the EditText is empty.How to do this ?

This is my code for button click

ImageButton imb=(ImageButton)findViewById(R.id.btn_send);
            imb.setOnClickListener(new OnClickListener()
            {
             @Override
             public void onClick(View arg0) 
             { 
                 EditText et = (EditText)findViewById(R.id.EditText1);

                  String str = et.getText().toString();
                  web1.add(str);
                  Toast.makeText(ShoutSingleProgram.this, "You entered...."+str, Toast.LENGTH_SHORT).show();
                  adapter1.notifyDataSetChanged();
                  et.setText("");

                    }
            });
            }

How can i do this ?

Answer 1

    editText1.addTextChangedListener(new TextWatcher() {

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

           if(s.toString().trim().length()==0){
                button.setEnabled(false);
              } else {
                button.setEnabled(true);
              }
        }

        @Override
        public void beforeTextChanged(CharSequence s, int start, int count,
                int after) {
            // TODO Auto-generated method stub

        }

        @Override
        public void afterTextChanged(Editable s) {
            // TODO Auto-generated method stub

        }
    });

Answer 2

Use TextChangedListener and initially disable ImageButton in onCreate().

Try this

public class MyActivity extends Activity {

ImageButton imb;
EditText et;

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

    imb = (ImageButton) findViewById(R.id.btn_send);
    et = (EditText) findViewById(R.id.EditText1);

    imb.setEnabled(false); // set button disable initially

    et.addTextChangedListener(new TextWatcher() {

        @Override
        public void onTextChanged(CharSequence s, int start, int before,
                int count) {
            // TODO Auto-generated method stub

            if (s.toString().equals("")) {
                imb.setEnabled(false);
            } else {
                imb.setEnabled(true);
            }
        }

        @Override
        public void beforeTextChanged(CharSequence s, int start, int count,
                int after) {
            // TODO Auto-generated method stub

        }

        @Override
        public void afterTextChanged(Editable s) {
            // TODO Auto-generated method stub

        }
    });

}

}

Answer 3

Simple just check the condition in onCreate

if (et.getText().toString().trim().equals("")){
  button.setEnabled(false);
}
else{
button.setEnabled(true);
}

Answer 4

Easy Solution

This is very easy to implement in Data-Binding . I hope you are aware of it at this time. You can manage Button with EditText via only XML.

android:enabled="@{etName.text.length() > 0 && etPassword.text.length() > 5}"

Which is equivalent to

button.setEnabled(etName.getText().length() > 0 && etPassword.getText().length() > 5 );

• Here & is HTML entity which denotes to & . There can be any operator like &.

• etName & etPassword are EditTexts ids.

Complete XML -

<LinearLayout
    >

    <EditText
        android:id="@+id/etName"
        />

    <EditText
        android:id="@+id/etPassword"
        />

    <Button
        android:enabled="@{etName.text.length() > 5 &amp;&amp; etPassword.text.length() > 5}"
        />

</LinearLayout>

Answer 5

I used TextUtils for a concise solution:

    editText.addTextChangedListener(new TextWatcher() {
        @Override
        public void onTextChanged(CharSequence s, int start, int before, int count) {
            button.setEnabled(!TextUtils.isEmpty(s.toString().trim()));
        }

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

        @Override
        public void afterTextChanged(Editable s) {
        }
    });

Answer 6

Here's a super simple answer in Kotlin.

Just replace 'EditText' and 'Button' with your own.

Button.isEnabled = false
        EditText.addTextChangedListener(object: TextWatcher {
            override fun onTextChanged(s:CharSequence, start:Int, before:Int, count:Int) {
                Button.isEnabled = s.toString().trim{ it <= ' ' }.isNotEmpty()
            }
            override fun beforeTextChanged(s:CharSequence, start:Int, count:Int,
                                           after:Int) {
            }
            override fun afterTextChanged(s: Editable) {
            }
        })

For Multiple EditTexts go

Button.isEnabled = false
            val editTexts = listOf(editText1, editText2, editText3, editText4, editText5, editText6)
for (editText in editTexts) {
            editText.addTextChangedListener(object : TextWatcher {
            override fun onTextChanged(s: CharSequence, start: Int, before: Int, count: Int) {
                var et1 = editText1.text.toString().trim()
                var et2 = editText2.text.toString().trim()
                var et3 = editText3.text.toString().trim()
                var et4 = editText4.text.toString().trim()
                var et5 = editText5.text.toString().trim()
                var et6 = editText6.text.toString().trim()

                computeBtn.isEnabled = et1.isNotEmpty()
                        && et2.isNotEmpty()
                        && et3.isNotEmpty()
                        && et4.isNotEmpty()
                        && et5.isNotEmpty()
                        && et6.isNotEmpty()
            }

            override fun beforeTextChanged(
                s: CharSequence, start: Int, count: Int, after: Int) {
            }

            override fun afterTextChanged(
                s: Editable) {
            }
        })
        }

Answer 7

将 TextWatcher 添加到您的 EditText，以便当您更改其中的文本时，您 Button 会启用或禁用自身。

Answer 8

Initally in onCreate() disable the button. Then add a addTextChangedListener to the edit text. within that check the edittext length and disable if it is 0 or otherwise enable it

Answer 9

on Oncreate() , before button click you should check the condition as,

   ImageButton imb=(ImageButton)findViewById(R.id.btn_send);
   EditText et = (EditText)findViewById(R.id.EditText1);
   if(et.getText().toString().equals("")
   {
   imb.setEnabled(false);
   }

   imb.setOnClickListener(new OnClickListener()
        {
         @Override
         public void onClick(View arg0) 
         { 
             EditText et = (EditText)findViewById(R.id.EditText1);

              String str = et.getText().toString();
              web1.add(str);
              Toast.makeText(ShoutSingleProgram.this, "You entered...."+str, Toast.LENGTH_SHORT).show();
              adapter1.notifyDataSetChanged();
              et.setText("");

                }
        });

Answer 10

When you want to disable the editText there You will use below code

editText.setEnabled(false); 
editText.setFocusable(false);

Answer 11

you check the status of an edittext at runtime using the text watcher. the below code counts the text length and disables if the length is zero. use this code:

EditText mEditText = new EditText(this);
    mEditText.addTextChangedListener(new TextWatcher() {

        @Override
        public void onTextChanged(CharSequence s, int start, int before,
                int count) {
            // TODO Auto-generated method stub
            if (s.length() == 0) {
                button.setEnabled(false);
            }
                            else {
                            button.setEnabled(true);
                        }
        }

        @Override
        public void beforeTextChanged(CharSequence s, int start, int count,
                int after) {
            // TODO Auto-generated method stub

        }

        @Override
        public void afterTextChanged(Editable s) {
            // TODO Auto-generated method stub

        }
    });

Answer 12

If you want to use an object oriented solution and reuse your code

public abstract class EmptyTextWatcher implements TextWatcher
{
    public abstract void onEmptyField();

    public abstract void onFilledField();

    @Override
    public void onTextChanged(CharSequence s, int start, int before, int count)
    {
        if (s.toString().trim().length() == 0)
        {
            onEmptyField();
        } else
        {
            onFilledField();
        }
    }

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

    }



    @Override
    public void afterTextChanged(Editable s)
    {

    }

}

so you can use it just doing

textView.addTextChangedListener(new EmptyTextWatcher()
        {

            @Override
            public void onEmptyField()
            {
                button.setEnabled(false);
            }

            @Override
            public void onFilledField()
            {
                button.setEnabled(true);
            }
        });

Answer 13

if anyone was wondering here is the kotlin version of the code

editText1.addTextChangedListener(object: TextWatcher {
        override fun onTextChanged(s:CharSequence, start:Int, before:Int, count:Int) {
            if (s.toString().trim({ it <= ' ' }).isEmpty())
            {
                button.setEnabled(false)
            }
            else
            {
                button.setEnabled(true)
            }
        }
        override fun beforeTextChanged(s:CharSequence, start:Int, count:Int,
                              after:Int) {
            // TODO Auto-generated method stub
        }
        override fun afterTextChanged(s: Editable) {
            // TODO Auto-generated method stub
        }
    })

Answer 14

Same as the top accepted answer, but simplified. Remember to wrap the condition in () so it uses the boolean.

editText1.addTextChangedListener(new TextWatcher() {

    @Override
    public void onTextChanged(CharSequence s, int start, int before, int count) {
         button.setEnabled((s.toString().trim().length()>0));     
    }

    @Override
    public void beforeTextChanged(CharSequence s, int start, int count,
            int after) {
        // TODO Auto-generated method stub

    }

    @Override
    public void afterTextChanged(Editable s) {
        // TODO Auto-generated method stub

    }
});