使用onClickListener时出错（意图）

Question

Well, I'm trying to create an intent on a "login.java" the code is :

 Button btEntrar = (Button) findViewById(R.id.btnSingIn);
    btEntrar.setOnClickListener(new View.OnClickListener() {
        @Override
        public void onClick(View v) {
            Intent i;
            i = new Intent(this, MainActivity.class);
            startActivity(i);


        }
    });

But it says that I can't go to the other activity saying this :

Error:(24, 21) error: no suitable constructor found for Intent(,Class) constructor Intent.Intent(String,Uri) is not applicable (argument mismatch; cannot be converted to String) constructor Intent.Intent(Context,Class) is not applicable (argument mismatch; cannot be converted to Context)

and...

Error:Execution failed for task ':app:compileDebugJava'. Compilation failed; see the compiler error output for details.

Answer 1

Just a few lines to explain the reason why this does not work in:

i = new Intent(this, MainActivity.class)

The intent is created inside another class, here an anonymous inner class OnClickListener . Thus this does not refer the instance of your Activity (or Context) as intended but the instance of your anonymous inner class OnClickListener .

So you should provide the correct context of your class.

i = new Intent(YourClassName.this, MainActivity.class)

Answer 2

use if you want to send it from login.java to mainactivity.class use

 Intent intent=new Intent(login.this,Mainactivity.class);
startActivity(intent);

Answer 3

updated code in to your activity

Button btEntrar = (Button) findViewById(R.id.btnSingIn);
 btEntrar.setOnClickListener(new View.OnClickListener() {
    @Override
    public void onClick(View v) {
        Intent i;
        i = new Intent(login.this, MainActivity.class);
        startActivity(i);


    }
});

Answer 4

try using

Intent i = new Intent(login.this, mainActivity.class);

hope this helps

Answer 5

您是否添加了manifest.xml或尝试此代码？
Intent i = new Intent(login.this,mainActivity.class);