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Android Build a Simple Android App Basic Android Programming Adding the OnClick Method

Kendall Chung
Kendall Chung
9,511 Points

cant run my app

hey guys, for some reason I cannot run my app. here are the details of the errors. there are 3 errors preventing me from running the app.

Information:Gradle tasks [:app:assembleDebug] Error:(32, 24) error: method setOnClickListener in class View cannot be applied to given types; required: OnClickListener found: no arguments reason: actual and formal argument lists differ in length Error:(22, 53) error: cannot find symbol variable ShowFactButton Error:Execution failed for task ':app:compileDebugJavaWithJavac'.

Compilation failed; see the compiler error output for details.

Thanks guys!

Kendall Chung
Kendall Chung
9,511 Points

package kendall.funfacts;

import android.content.DialogInterface; import android.support.v7.app.AppCompatActivity; import android.os.Bundle; import android.view.View; import android.widget.Button; import android.widget.TextView;

public class FunFactsActivity extends AppCompatActivity { // Declare Our Views variables private TextView mFactTextView; private Button mShowFactButton;

protected void onCreate(Bundle savedInstanceState) {

    //Assign the Views from the layout file to the corresponding variables
    mFactTextView = (TextView) findViewById(R.id.factTextView);
    mShowFactButton = (Button) findViewById(R.id.ShowFactButton);

    View.OnClickListener listener = new View.OnClickListener() {
        public void onClick(View v) {
            String[] facts= {
                    "Ants stretch when they wake up in the morning.",
                    "Ostriches can run faster than horses.",
                    "Olympic gold medals are actually made mostly of silver.",
                    "You are born with 300 bones; by the time you are an adult you will have 206.",
                    "It takes about 8 minutes for light from the Sun to reach Earth.",
                    "Some bamboo plants can grow almost a meter in just one day.",
                    "The state of Florida is bigger than England.",
                    "Some penguins can leap 2-3 meters out of the water.",
                    "On average, it takes 66 days to form a new habit.",
                    "Mammoths still walked the earth when the Great Pyramid was being built." };

            // The button was clicked, so update the fact TextView with a new fact
            String fact = "";
            // Randomly select a fact
            Random randomGenerator = new Random();
            int randomNumber = randomGenerator.nextInt(10);
            fact = facts[randomNumber];

            // Update the screen with our dymanic fact



1 Answer

Kourosh Raeen
Kourosh Raeen
23,733 Points

The id of the mShowFactButton button should be showFactButton, with a lower-case s:

mShowFactButton = (Button) findViewById(R.id.showFactButton);

Also, you need to pass the OnClickListener listener to the setOnClickListener() method: