如何使用图像选择器将照片发送到hp彩色打印机

Question

我将一些图像发送到firebase存储，然后另一个获取图像并需要将其打印在相纸上。我可以使用什么样的颤振API。

我已经设法使用methodchannel调用了本机api，并且在重定向到打印服务时似乎是这样。但它只进入打印服务，在那里我必须点击打印，而不是直接启动打印。

请添加您对如何直接启动打印的建议。

Answer 1

package com.example.print1
import android.content.Context
import android.content.ContextWrapper
import android.content.Intent
import android.content.IntentFilter
import android.os.BatteryManager
import android.os.Build.VERSION
import android.os.Build.VERSION_CODES
import androidx.annotation.NonNull
import io.flutter.embedding.android.FlutterActivity
import io.flutter.embedding.engine.FlutterEngine
import io.flutter.plugin.common.MethodChannel
import android.R
import androidx.print.PrintHelper
import android.graphics.BitmapFactory
import android.R.drawable
class MainActivity : FlutterActivity() {
private val CHANNEL = "samples.flutter.dev/battery"
override fun configureFlutterEngine(@NonNull flutterEngine: FlutterEngine) {
super.configureFlutterEngine(flutterEngine)
MethodChannel(flutterEngine.dartExecutor.binaryMessenger, CHANNEL).setMethodCallHandler {
// Note: this method is invoked on the main thread.
call, result ->
if (call.method == "Printphoto") {
doPhotoPrint()
} else {
result.notImplemented()
}
}
}

private fun doPhotoPrint() {
println("heloo the yout");
activity.also { context ->
PrintHelper(context).apply {
scaleMode = PrintHelper.SCALE_MODE_FIT
}.also { printHelper ->
val bitmap = BitmapFactory.decodeResource(resources, R.drawable.alert_dark_frame)
printHelper.printBitmap("droids.jpg - test print", bitmap)
}
}
}
}

static const platform = const MethodChannel('samples.flutter.dev/battery');
String _printstatus =       'printing photo';
Future<void> Printphotocall() async {
String batteryLevel;
try {
final int result = await platform.invokeMethod('doPhotoPrint');
_printstatus = 'Battery level at $result % .';
} on PlatformException catch (e) {
_printstatus = "Failed to print: '${e.message}'.";
}
setState(() {
_printstatus = batteryLevel;
});
}