Android studio button has no onclick option error message box-CodePudding

I'm currently learning to make apps in android studio. When I drag a button object into the activity_main.xml,it does not show me the "onclick" option under the "Declare Attributes".

The only error I'm getting is :

Couldn't resolve resource @color/teal_200 I dont think it has anything to do with my problem but still...

Any help would be appriciated,thank you!

CodePudding user response：

Add it via xml.

You'll find your button in there, declared like this:

<Button
    android:id="@ id/button"
    android:onClick="doSomething"
    ... />

Nevertheless, it's better style to get the button by id and apply an OnClickListener:

Button button = findViewById(R.id.button);
button.setOnClickListener(() -> {
    System.out.println("Clicked");
});

The color-error is caused by a missing color in res/values/colors.xml.

You'll have to add your color there like this:

<resources>
    <color name="errorRed">#FF0033</color>
</resources>

CodePudding user response：

make sure for when declaring color in your xml file you use

android:textcolor="@color/white" // for text color android:backgroundTint="@color/black" // for button background color

also in your activitymain.java I find it easier declaring your onclicks there

public class MainActivity extends AppCompatActivity {
Button buttonnamegoeshere;



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



}
buttonnamegoeshere.setOnClickListener(new View.OnClickListener() {
    @Override
    public void onClick(View v) {
        //button code goes hereenter code here
    }
});

}

Hope this helps!