如何使用图像选择器将照片发送到我的 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 Flutter API。

我已经设法使用方法通道调用本机 api，它似乎在重定向到打印服务。但它只进入打印服务，我必须点击打印并且不直接启动打印。

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;
        });
      }