在使用intent共享数据时，我们可以将所需的全部类型都打包于ShareCompt类中
在数据类型中，有一种类型叫媒体类型 Media Type String，媒体类型字符串由类型，子类型和可选参数组成。例如text/html; charset = URF-8

当你想在应用之间共享数据时 ，你必须说明它的媒体类型。以使android确定如何以及是否可以完成请求。

String mimeType = "text/plain";
String title = "Learning  How to Share"
String textToShare  = "Hello there"
ShareCompat.IntentBuilder.from(this).setChooserTitle(title).setType(mimeType).setText(textToShare).startChooser();;

public class DetailActivity extends AppCompatActivity {

    private static final String FORECAST_SHARE_HASHTAG = " #SunshineApp";

    private String mForecast;
    private TextView mWeatherDisplay;

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

        mWeatherDisplay = (TextView) findViewById(R.id.tv_display_weather);

        Intent intentThatStartedThisActivity = getIntent();

        if (intentThatStartedThisActivity != null) {
            if (intentThatStartedThisActivity.hasExtra(Intent.EXTRA_TEXT)) {
                mForecast = intentThatStartedThisActivity.getStringExtra(Intent.EXTRA_TEXT);
                mWeatherDisplay.setText(mForecast);
            }
        }
    }

    private Intent createShareForecastIntent() {
        Intent shareIntent = ShareCompat.IntentBuilder.from(this)
                .setType("text/plain")
                .setText(mForecast + FORECAST_SHARE_HASHTAG)
                .getIntent();
        return shareIntent;
    }

    @Override
    public boolean onCreateOptionsMenu(Menu menu) {
        getMenuInflater().inflate(R.menu.detail, menu);
        MenuItem menuItem = menu.findItem(R.id.action_share);
        menuItem.setIntent(createShareForecastIntent());
        return true;
    }
}